http://breezewiki.pjsfkvpxlinjamtawaksbnnaqs2fc2mtvmozrzckxh7f3kis6yea25ad.onion/minecraft/wiki/Dropper
For example, to lock a dropper at (0,64,0) so that only players holding an item named "Alice's Key" can access the dropper, use / data merge block 0 64 0 {Lock:"Alice's Key"} . [ Java Edition only ] Redstone component See also: Redstone circuit A dropper can be used to eject items, or push items into another container.